This invention relates generally to the art of spray head assemblies and more particularly to spray head assemblies used on, or in connection with, dishwashing installations.
A spray head assembly that relates to this invention is described in U.S. Pat. No. 4,527,743 to Ettlinger et al. The spray head assembly described in that patent includes a seesaw actuator lever arm having an actuator shaft which extends into a water-sealed spray-head compartment from which water is sprayed through spray pores. The actuator lever arm is pivoted so that the actuator shaft slides a sliding valve plate in the water-sealed spray-head compartment to allow pressurized water from a supply pipe to enter the spray-head compartment through a hole in the sliding valve plate. In this patent, the actuator lever arm is elongated and extends along the supply pipe, with a handle of the actuator lever arm being adjacent to the pipe. In order to turn on the spray head assembly of the Ettlinger et al. device the handle is squeezed toward the supply pipe. The actuator lever pivots to move the actuator shaft thereof in the spray-head compartment and to also move the sliding valve plate laterally which, in turn, registers the hole of the valve plate with a water-supply passage of the supply pipe, thereby allowing water to enter the spray-head compartment and be sprayed from the spray pores.
Although the spray head assembly of the Ettlinger et al. patent has many advantages over prior art spray head assemblies for washing dishes and the like, it has the problem that the sliding valve plate does not adequately seal the mouth of the water-supply passageway when the spray head assembly is not turned on. That is, water pressure within the water-supply passageway of the supply pipe can get around the sliding valve plate and can either pass through a rubber, sealing, bulkhead or drip from the spray pores of the spray-head compartment, neither of which is desirable. Although attempts have been made to improve the mechanism of Ettlinger et al. so that the sliding valve plate forms a better seal at the mouth of the supply pipe, to date such efforts have not resulted in a totally satisfactory mechanism. Although one attempt to improve the seal did help control the water, it unduly increased the amount of force required to actuate the actuator lever arm in order to slide the valve plate.
In any event, it is an object of this invention to provide a spray head assembly for use in dishwashing and the like which more positively controls, both cutting on and cutting off, water coming from a supply pipe without the necessity of an operator using an undue force to actuate it.
Further, it is an object of this invention to provide a spray head assembly as mentioned in the previous paragraph which is relatively uncomplicated in structure and which can be manufactured in a relatively cost-effective manner.